Caspian Tern Identification

Breeding adult

The largest tern in the world. Note large red bill, tail with only a shallow fork, and black on the underside of outer primary feathers. Breeding adults have a fully black cap.

Breeding adult

Note massive, bright-red bill, sometimes with black tip. Breeding adults have fully black cap, sometimes raised in a short crest.

Breeding adults and juvenile with Laughing Gulls

Note big, thick-based red bill, thick neck, and squared off or slightly crested head. Juveniles are camouflaged with grayish or brownish markings on the back.

Nonbreeding adult

Large tern with very large bill. Nonbreeding adults have a grayish crown and reduced black on the head.

Juvenile

Large tern with large reddish bill. Juveniles have brownish markings on the back and a brown-black crown that is often streaky on the forehead.

Breeding adult

Juvenile

Breeding adult

Large tern with massive, red, pointed bill. The large head can look smoothly rounded, squared off, or slightly crested. The outer primaries are dark, especially on the undersides.

Nonbreeding adult

Very large tern with broad wings and large, red bill. Undersides of outer primary feathers are dark. Nonbreeding adults and immatures have variable amounts of white on the forehead. Gaps in the wings usually are a sign that the bird is molting.

Juvenile

Flock

Occurs along seacoasts, barrier islands, estuaries, and saltmarshes, as well as some inland lakes and rivers.